A recurrent de novo variant (AP2M1:c.508C>T, p.Arg170Trp) was functionally demonstrated in four unrelated female individuals associated with GDD (4/4), autism spectrum disorder (2/4), and the electroclinical phenotype known as myoclonic–atonic seizures or Doose syndrome (3/4).1 The gene discussed is AP2M1; the disease is Global developmental delay.